ギムレー, Grima, Evil Dragon (邪竜), Fell Dragon, The Creation (造られしもの), Hierophant
Grima is the true main antagonist in Fire Emblem Awakening and a secret boss in Fire Emblem Echoes: Shadows of Valentia. Grima tends to go by the title of the Fell Dragon and is feared by most of the world. Source: Fire Emblem Wikia